<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        // 返还函数
        // var arr=[1,2,3,4,5,6]
        // var res=arr.reverse();
        // console.log(res);//正序变成倒序；
        // 返还字符串
        var str="abcdefg";
        console.log(str.split(""));
        var res = str.split("").reverse();
    </script>
</body>
</html>